India Choking: Factors spreading air pollution and abatement techniques to be learned from China

The cold fact is that toxic air is a side effect of industrialisation. It has long been the collateral damage of development. But can a nation become economically advanced without polluting? The nations of the West do not provide examples that the developing countries of Asia can follow, without polluting copious and damaging amounts.

This is part two of a three-part series on the rise of Air Pollution in India. The series hopes to address the severity of the air pollution problem and what are the measures that can be used to mitigate the same. You can read the first part of the story here

By Pallavi Aiyar

The path to blue skies is littered with horror stories, even for the countries that are today rich and clean. One example is the small industrial town of Donora, Pennsylvania, in the United States, where a putrid fog in October 1948 killed 20 people and led to the hospitalisation of 7,000 others. The reason: a weather anomaly that trapped toxic emissions from the town’s zinc smelting plant close to the ground. The Donora disaster brought air pollution into focus in the United States, and paved the way for mitigating legislation.

The cold fact is that toxic air is a side effect of industrialisation. It has long been the collateral damage of development. But can a nation become economically advanced without polluting? The nations of the West do not provide examples that the developing countries of Asia can follow, without polluting copious and damaging amounts.

However, research on the effects and mitigation of pollution exists today, unlike during Europe’s industrialisation. Technologies, including pollution abatement equipment, renewable energy and better-grade fuel are available. Moreover, even developing nations have substantial urban middle-classes for whom making a daily wage is no longer the driving force of life – allowing health to become a motivating concern.

For India, China is the contemporary example to learn from. Although Beijing remains synonymous with toxic skies in the international imagination, China has actually undertaken far-reaching measures to ensure that the worst may be over.

Technologies for cleaning the air range from the expensive and high tech, to basic, low cost ones. Let’s explore some technological solutions that address industrial, vehicular and construction-related pollution.

Pollution abatement techniques used in China

Sulfur Dioxide (SO2) is one of the most toxic elements of air pollution, linked to permanent lung damage. Coal and oil-fired power plants, steel mills, refineries, pulp mills, and smelters are amongst the largest releasers of SO2 since they operate by burning fuels like coal, oil and diesel that contain sulfur.

China’s overall SO2 levels decreased by 14.8 percent between 2006-2010, and even more steeply since – mostly as a result of the installation of pollution abatement equipment on its thermal power plants. This equipment includes devices called “scrubbers” which can remove up to 95 percent of SO2 emissions. China has in fact emerged as a leading producer of pollution-abatement equipment and is currently upgrading its plants to enable them to remove even higher levels (up to 97 percent) of SO2 from emissions.

India Choking: Factors spreading air pollution and abatement techniques to be learned from China

Image: Reuters

Nitrogen Oxides (NOx) are also major industrial pollutants, linked to wheezing, bronchitis and heart conditions. But their emissions can be controlled via several techniques. A simple modification of the combustion process can result in 30-50 percent decreases in NOx output. A more expensive option called selective catalytic reduction can reduce emissions by 80-90 percent.

It’s important to point out that SO2 and NOx also produce PM 2.5, the pollutant we know to have the worst health effects, indirectly, under the right atmospheric conditions.

In China, NOx pollution abatement equipment on power plants was made mandatory in 2014, one of the main reasons why pollution levels in 2015 registered a dip. According to a Greenpeace report there was a 10 percent reduction countrywide in the intensity of smog in 2015 over 2014.

There are several other technologies with jargonistic titles like integrated gasification combined cycles and electrostatic precipitators as well. Combined, these technologies are referred to as “clean coal,” and for a country like India, where nearly two-thirds of the power still comes from coal, there is an urgent need to embrace them.

Much to learn from China

For the moment however, India lags far behind China. One example: the share of thermal power plants with basic pollution abatement equipment in China is 95 percent compared to only 10 percent in India.

Other technological solutions involve stricter emissions norms for cars and the availability of appropriate fuel to power them. From this year all vehicles across China must comply with the country’s fifth set of emissions standards (Beijing, Shanghai, Nanjing and some cities in Guangdong have already enforced these), which are equivalent to Euro V standards, where the maximum sulfur content permitted for both diesel and petrol is at 10ppm (parts per million).

Image: Reuters

Image: Reuters

By contrast, in most parts of India only Euro III norms are followed, (sulfur content of diesel allowed at 350 ppm and 150 ppm for petrol). Thirteen major cities however already have norms equivalent to Euro IV (which mandates sulfur content for both petrol and diesel at 50ppm).

Last year, the government announced that India would skip level V norms altogether and adopt Euro VI-equivalent standards by 2020. These would lower the permitted level of NOx for diesel emissions to a maximum of 80mg/km, compared to the 180mg/km under Euro V.

For India, the challenge will be to ensure that higher grade fuel is available because high sulfur content in the fuel inhibits the proper functioning of anti-vehicular pollution technologies like special filters that reduce diesel particulates. China’s oil industry already produces petrol and diesel suitable for vehicles that operate on a Euro V standard.

Construction dust

Image: Reuters

Image: Reuters

Finally, lower tech, but equally valuable solutions have to do with better management of construction activity, which is a major source of PM 10. Dust from concrete, stone, cement, sand and wood irritates the nose and chest. It can also travel over large distances depending on the windspeed. Building materials transported in uncovered vehicles or left in the open outside construction sites, common practices in India, are amongst the worst offenders when it comes to coarse particles. The problem is only set to intensify given that seventy to eighty percent of the India of 2030 is yet to be built.

Some measures to help control the resultant pollution include making sure that trucks loaded with construction materials are covered, as are building materials like cement and sand. In general, building sites should use fine water sprays to dampen down the site.

The authour recently wrote the book ‘Choked: Everything You Were Afraid to Know About Pollution’

This is part two of a three-part series on the rise of Air Pollution in India. The series hopes to address the severity of the air pollution problem and what are the measures that can be used to mitigate the same. You can read the first part of the story here

The next piece in this series will look at the relationship between air pollution and the individual, including how technology can help to protect us from the worst health effects.

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